How much do I need to worry about leucine and MPS?

[opf]

Hi Jordan

I just now learned that a meal has to have at least 3 grams of leucine in order to trigger muscle protein synthesis. But then at the same time I see you (BBM that is) hinting that we do not need to worry about that as long as we get an adequate amount of protein. But that confuses me - the fact that ~3 grams of leucine is needed to trigger MPS is either true or false. If true - and if it’s also true that MPS is needed to build muscle - how is this not something that I should take into account?

To be very specific:

I usually have about 200-250 grams of low fat greek yoghurt before bed. That’s not 3 grams of leucine. Maybe 2-2.5. Is this serving of protein pointless for building muscle since it does not trigger MPS? If answer is no - how is it not pointless?

I hope you can clear things up a bit

thanks in advance

[Jordan Feigenbaum]

I wouldn't worry about it at all and given the timing of the meal, it likely does contribute to a MPS event. If not, it'll contribute to one in the future. No biggie.

Also, I think there may be a misunderstanding here with regards to dosing. It doesn't take at least 3g of leucine to trigger MPS, but rather to max it out (in most situations). You can trigger MPS significantly with less.

[opf]

Why would you not worry about it? Isn't MPS needed to build muscle - so why would I not worry about it being present? Is it because no one really knows for certain how much leucine exactly is needed to drive MPS? Or does MPS happen at lower doses of leucine just not as "powerful"? Also does leucine from one meal "stick around" in the body and contribute to a future leucine "spike"? And is that why you would not worry about this too much?

I should mention that I don't really eat meat but do eat tons of greek yoghurt, eggs, cheese, whey etc. Another staple of mine is 3 egg omelet with some cheese on toasted bread with butter or avocado. But that doesn't add up to 3 grams of leucine either. I just feel like there are a lot of meals that I eat during the day that just barely hit the 3 g leucine target. And I'm still not sure why I should not worry about it

[Jordan Feigenbaum]

Why would you not worry about it?

Because if you're eating a protein-rich diet, none of this matters.

Is it because no one really knows for certain how much leucine exactly is needed to drive MPS?

It's just variable in individuals and in situations. I wouldn't/didn't say MPS only occurs with 3g of leucine in a meal at all times for everyone, but at this dose, nearly everyone (even untrained, sedentary, and/or anabolically resistant individuals) will have the maximal MPS response. Less is needed to trigger MPS.

Or does MPS happen at lower doses of leucine just not as "powerful"?

It can to a point, but not my much.

Also does leucine from one meal "stick around" in the body and contribute to a future leucine "spike"? And is that why you would not worry about this too much?

As I said in my previous reply, it can.

I should mention that I don't really eat meat but do eat tons of greek yoghurt, eggs, cheese, whey etc. Another staple of mine is 3 egg omelet with some cheese on toasted bread with butter or avocado. But that doesn't add up to 3 grams of leucine either. I just feel like there are a lot of meals that I eat during the day that just barely hit the 3 g leucine target. And I'm still not sure why I should not worry about it

Because you're eating enough protein to where a single meal's leucine content is irrelevant from a muscle gain standpoint. When investigating added leucine to a diet already high (but much lower than yours) in protein, there's no added benefit to muscle cross sectional area. MPS is a biochemical reaction that we use as a surrogate for increased muscle size, but this doesn't really have a 1:1 relationship, at least not as far as we can tell.

You're free to add more protein to your diet if you want, but worrying about MPS from a single meal is almost as catabolic as worrying about testosterone levels.

[opf]

Makes sense. Thanks for a more in depth explanation. Seems to be somewhat uncertain/speculative territory still. I'll stop worrying too much about it. Thank you

[Jordan Feigenbaum]

Makes sense. Thanks for a more in depth explanation. Seems to be somewhat uncertain/speculative territory still. I'll stop worrying too much about it. Thank you

I don't know that it's fair to call it speculative or suggest the uncertainty is greater than other well-described scientific concepts.